The various cost elements need to be added up to give you the total cost of your contract over its term.

To get the best iPhone 4 deal you’ll obviously need to consider your particular needs, for example how much time do you spend talking vs sending texts?

Critically also consider your data allowance. Until recently on the 3G network data was generally unlimited but most providers have now capped their data allowance.

With O2, Tesco, 3 and Vodafone capping their data between 500MB and 1GB per month, you might be wondering is this enough? The answer is that for most people it will be – you’ll be able to surf the web for a few hours, send and receive a number of emails with attachements, download a small number of music tracks and watch a small amount of video.

Clearly you need to think carefully about your monthly data requirements – and what’s been found so far is that iPhone users tend to use more data than originally anticipated.

At the time of writing, Orange, O2, Vodafone, 3 and Tesco all have a range of iPhone 4 tariffs.

Based on a black 16GB phone, some of the best iPhone 4 deals we could find as at 26 May 2011 include

Network

Contract Length

Phone Cost

Monthly Cost

No of Minutes

No of Texts

Data Allowance

Total Cost

Tesco

12

£342.00

£25

250

5000

1Gb

£642.00

Tesco

12

£235.00

£40

750

5000

1Gb

£715.00

Vodafone

12

£239.00

£40

600

Unlimited

500MB

£719.00

O2

18

£140.99

£36

600

Unlimited

500MB

£788.99

Vodafone

18

£199.00

£35

300

Unlimited

500MB

£829.00

Orange

18

£229.99

£35

600

500

500MB

£859.99

O2

18

Free

£62.00

Unlimited

Unlimited

1Gb

£1,116.00

Vodafone

18

Free

£45

900

Unlimited

1Gb

£810.00

3

24

£69

£35

2000 (5000 3-to-3)

5000

All-you-can-eat Data

£909.00

O2

24

100.99

£36

900

Unlimited

500MB

£964.99

Vodafone

24

£139

£35

600

Unlimited

500MB

£979.00

Orange

24

£119.99

£35

600

Unlimited

500MB

£959.99

Vodafone

24

Free

£40

900

Unlimited

750MB

£960.00

3

24

Free

£43

900

5000

1GB

£1032.00

Tesco

24

£19

£45

3000

5000

1GB

£1,099.00

Orange

24

Free

£50

1200

Unlimited

1GB

£1,200.00

As you can see there are limited deals available on a 12 month contract but if you’re prepared to opt for a 24 month contract there are plenty of options.

We’ve highlighted the different plans at the £35 a month level and as you can see a differentiator is the minutes allowance, although with Vodafone offering a deal to check.